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This study aimed to assess volatile impurities and ethanol content in ethanol-based hand sanitizers. A total of 31 different brands of hand sanitizers were analyzed using headspace gas chromatography-mass spectrometry to detect impurities and determine alcohol content for compliance. Volatile impurities were identified through Mass Spectrometry database analysis, and regression analysis was employed to ascertain ethanol percentage. Furthermore, a simulated toxicological analysis was conducted to evaluate the potential toxic effects associated with hand sanitizer usage. The detected impurities primarily included ethyl acetate, benzene, acetone, and acetal, along with contaminations such as isobutanol and non-recommended alcohols. In addition, 71 % of samples contained less than the recommended 60 % v/v alcohol concentration, failing to comply with guidelines from the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). Additionally, the simulation study underscored acute and chronic toxicities primarily linked to benzene contamination. Given that some of the studied products are imported while others are locally produced, it is imperative for consumers worldwide to be informed that certain hand sanitizers may not only be ineffective but also contain harmful residues.

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Several outbreaks of Listeria monocytogenes originated mainly from contaminated contact surfaces. Thus, this study investigated the antilisterial effect of natural surfactants in terms of their use as a 2-in-1 sanitizing washer on a food contact surface and evaluated their modes of action. The antilisterial activity of alkyl polyglycosides (APGs), namely capryl glucoside (CA), coco glucoside (CG), and decyl glucoside (DG), was evaluated based on the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) using broth dilution assay. The results showed that CG had the strongest antilisterial activity. Therefore, CG was selected for further investigation. The time-kill assay showed a lethal effect of 0.5 % w/w CG by inactivating 4 Log reduction (99.99 %) of L. monocytogenes within 3 s. Furthermore, 1 % (w/w) CG with slight mechanical force in washing (by shaking) was efficient for sanitizing a stainless-steel coupon surface based on its ability to cause a total reduction of deposited L. monocytogenes (99.9 %) within 10 min. Scanning electron microscopy and applying Fourier-transform infrared spectroscopy revealed that CG chemically disrupted the cell wall and plasma membrane of L. monocytogenes within 5 min after a gentle wash. The results showed it had potent antimicrobial activity and was bactericidal against L. monocytogenes. Overall, our results supported the use of CG as a natural antibacterial surfactant to alter the chemical sanitizer and the possibility of its practical use in the food industry and for household use.

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BACKGROUND: Hand hygiene and double gloving practices during induction of general anesthesia can decrease transmission of bacteria to patients and subsequent healthcare associated infections; however, compliance to these practices is low. METHODS: A pre/post-implementation quality improvement design was used with Plan-Do-Study-Act cycles. Several implementation strategies were used to improve hand hygiene and double glove compliance among anesthesia providers, including printed educational materials, video, in-person, and virtual meetings, visual reminders, audit and feedback, and improved access to hand sanitizer dispensers in the anesthesia workstation. RESULTS: Average hand hygiene compliance increased from 0% to 11.8% and double gloving compliance increased from 18.5% to 34.5%. A decrease in surgical site infections was shown in the post-implementation period. DISCUSSION: Although hand hygiene and double gloving practices increased after the initial implementation, the improvements were not sustained long-term. Practices to support sustainability, such as routine booster sessions, may be considered. CONCLUSIONS: Incorporating these quality improvement measures into practice may improve anesthesia provider hand hygiene compliance during induction of general anesthesia and impact subsequent infection rates.

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Hands are in fact the main route of transmission of pathogenic infections. By using proper hand sanitization, we can break the virus's transmission chain, which is especially important in the ongoing COVID pandemic outbreaks. The effectiveness of hand sanitization is solely dependent on the use of sufficient antibacterial agents, which come in a variety of levels and types, including antimicrobials commercial, water-based, or alcohol-based hand sanitizer, the latter being widely used during pandemics. Therefore, the sudden overuse of sanitizers also could lead to an increase in the tolerance limit for normal hand flora and the new development of antimicrobial resistance (AMR). In this study, we investigated the relationship between hand sanitizer-tolerant bacteria and their antibiotic resistance profile to multiple antibiotic agents. On a timely basis before and after using different hand sanitizers, bacterial strains were collected from the volunteers of CSIR-Central Salt and Marine Chemicals Research Institute (CSIR-CSMCRI). Sanitizer tolerant bacterial strains were observed also just after the application of sanitizers, which also showed the AMR phenomenon. The resultant sanitizers' resistant microbiome showed the dominant presence of Bacillus sp., Staphyloccocus sp., Paenibacillus sp., Lysinibacillus sp., Exiguobacterium sp. and Leclercia sp. All 36 nos of bacterial strains showed MDR (> 5 nos).

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The recent rise in hand sanitizer use due to the COVID-19 pandemic has had a beneficial impact on stopping the spread of disease, but the potential negative implications of its overuse on the body and the microbiome have yet to be thoroughly reviewed. Epidermal layers absorb hand sanitizer from direct application to the skin, making them some of the most susceptible cells to the adverse effects of overuse. The increased usage of hand sanitizer can affect the variation, quantity, and diversity of the skin microflora, leading to conditions such as eczema, atopic dermatitis, and even systemic toxicity due to colonization of the skin with pathogenic bacteria. Due to the close-knit relationship between the skin and gut, the gastrointestinal system can also incur disruptions due to the negative effects on the skin as a result of excessive hand sanitizer use, leading to gut dysbiosis. Additionally, the accidental ingestion of hand sanitizer, and its abuse or misuse, can be toxic and lead to alcohol poisoning, which is an issue most commonly seen not only in the pediatric population but also in adolescents and adults due to aberrant recreational exposure. As a vulnerable body system, the eyes can also be negatively impacted by hand sanitizer misuse leading to chemical injury, visual impairment, and even blindness. In this review, we aim to highlight the variations in hand sanitizer formulation, the benefits, and how misuse or overuse may lead to adverse effects on the skin, gut, and eyes. In particular, we review the advantages and disadvantages of alcohol-based hand sanitizers (ABHSs) and non-alcohol-based hand sanitizers (NABHSs) and how the components and chemicals used in each can contribute to organ dysbiosis and systemic damage.

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Background: Antiseptics were introduced a long time ago, but their significance was noteworthy during the COVID-19 pandemic. Hand sanitizer plays a pivotal role as a preventive measure. Multiple national authorities have advocated for the application of Alcohol-Based Hand Sanitizers (ABHS). During the pandemic, a surge in demand and limited supply prompted numerous manufacturers to ramp up production. Consequently, it is imperative to scrutinize the composition, labeling, and price of hand sanitizers. Aims and Objective: To assess the contents, labeling, and price of hand sanitizers available in the Indian market. Methodology: Hand sanitizers, both online and offline, marketed in India between May 2019 and May 2022 were included. Hand sanitizers by local manufacturers without labeling were excluded. Contents and labeling of hand sanitizers were evaluated as per World Health Organization (WHO) recommendations. Price was assessed as a percentage cost variation. Result: Out of 79, the majority (98.73%) were ABHS, and 28.20% of them met the recommended criteria for "Adequate" alcohol concentration. Ethyl alcohol emerged as the most prevalent (69.23%), often accompanied by emollients, humectants, fragrances, and color additives. Notably, 69.62% of the hand sanitizers featured comprehensive labeling, while incomplete labels lacked essential details under "Warning and Cautions." The average price of hand sanitizers was Rs 505.11 ± 255.36. Conclusion: Choosing ABHS with appropriate alcohol concentrations in line with recommendations is crucial. To ensure the proper and safe use of hand sanitizers, individuals should follow the instructions provided on the product labels; both manufacturers and regulators are responsible for adhering to standards for hand sanitizers made available to the public.

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Bacteriophages (phages) have gained considerable attention as effective antimicrobial agents that infect and kill pathogenic bacteria. Based on this feature, phages have been increasingly used to achieve food safety. They are stored in a medium or buffer to ensure stability; however, they cannot be directly applied to food under these conditions due to reasons such as regulatory considerations and concerns about marketability. This study developed a stabilizing solution that allowed the maintenance of phage activity for extended periods at room temperature while being directly applicable to food. The stability of phages stored in distilled water was relatively low. However, adding a stabilizer composed of sugars and salts improved the survival rates of phages significantly, resulting in stability for up to 48 weeks at room temperature. When Escherichia coli O157:H7-contaminated vegetables were washed with tap water containing phages, the phages reduced the pathogenic E. coli count by over 90% compared with washing with tap water alone. Additionally, when pathogenic E. coli-contaminated vegetables were placed in a phage-coated container and exposed to water, the coating of the container dissolved, releasing phages and lysing the pathogenic E. coli. This led to a significant 90% reduction in pathogenic E. coli contamination compared to that after water rinsing. These results suggest an effective and economical method for maintaining phage activity and establishing the potential for commercialization through application in the food industry.

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The efficacy of a sanitizer in biofilm removal may be influenced by a combination of factors such as sanitizer exposure time and concentration, bacterial species, surface topography, and shear stresses. We employed an inline biofilm reactor to investigate the interactions of these variables on biofilm removal with chlorine. The CDC bioreactor was used to grow E. coli O157:H7 and L. monocytogenes biofilms as a single species or with Ralstonia insidiosa as a dual-species biofilm on stainless steel, PTFE, and EPDM coupons at shear stresses 0.368 and 2.462 N/m2 for 48 hours. Coupons were retrieved from a CDC bioreactor and placed in an inline biofilm reactor and 100, 200, or 500 ppm of chlorine was supplied for 1- and 4 min. Bacterial populations in the biofilms were quantified pre- and posttreatment by plating on selective media. After chlorine treatment, reduction (Log CFU/cm2) in pathogen populations obtained from three replicates was analyzed for statistical significance. A 1-min chlorine treatment (500 ppm), on dual-species E. coli O157:H7 biofilms grown at high shear stress of 2.462 N/m2 resulted in significant E. coli O157:H7 reductions on SS 316L (2.79 log CFU/cm2) and PTFE (1.76 log CFU/cm2). Similar trend was also observed for biofilm removal after a 4-min chlorine treatment. Single species E. coli O157:H7 biofilms exhibited higher resistance to chlorine when biofilms were developed at high shear stress. The effect of chlorine in L. monocytogenes removal from dual-species biofilms was dependent primarily on the shear stress at which they were formed rather than the surface topography of materials. Besides surface topography, shear stresses at which biofilms were formed also influenced the effect of sanitizer. The removal of E. coli O157:H7 biofilms from EPDM material may require critical interventions due to difficulty in removing this pathogen. The inline biofilm reactor is a novel tool to evaluate the efficacy of a sanitizer in bacterial biofilm removal.

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The significance of accurate determination of ethanol content in hydrogel formulations was accentuated during COVID-19 pandemic coinciding with the heightened demand for sanitizing agents. The present article proposes three robust methodologies for this purpose: Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Densitometry with matrix effect correction by Near-Infrared Spectroscopy (NIR). All three methods demonstrated outstanding linearity (R2 ≥ 0.99) and minimal errors (< 1.7%), offering simplicity and operational efficiency. FTIR and Raman, being non-destructive and requiring minimal preparation, enable practical on-site analysis capabilities, underscoring the potential of the spectroscopic methods to expedite health investigations and inspections, empowering on-site ethanol determination, and relieving the burden on official laboratories. Additionally, the densitometry with NIR-based approach showcased superior accuracy and precision compared to spectroscopic methods, meeting validation criteria while offering operational advantages over the costly official distillation-based method. Therefore, it stands as a reliable and reproducible technique for comprehensive health and criminal compliance assessments, making it a compelling alternative for both industry and official laboratories.

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Hydroponic farming systems play an increasingly important role in the sustainable production of nutrient-rich foods. The contamination of surfaces in hydroponic fresh produce production poses risks to the food safety of crops, potentially endangering public health and causing economic losses in the industry. While sanitizers are widely used in commercial hydroponic farms, their effectiveness against human pathogens on surfaces and their impact on plant health and quality are not known. In this study, we evaluated the efficacy of chemical sanitizers in eliminating Salmonella Typhimurium from inanimate surfaces in commercial hydroponic Nutrient Film Technique (NFT) systems. Further, we assessed the impact of sanitizers on the yield, quality, and nutritional value of lettuce and basil. Sanitizers (Virkon, LanXess, Pittsburgh, PA, USA; SaniDate 12.0, BioSafe Systems, East Hartford, CT, USA; KleenGrow, Pace Chemical Ltd., Delta, BC, Canada; Green Shield, United Labs Inc., St Charles, IL, USA; Zerotol, BioSafe Systems, East Hartford, CT, USA; Bleach, Pure Bright, ON, Canada) were tested against Salmonella Typhimurium inoculated on NFT surfaces (nutrient reservoir, growing channels, top covers, drain lines). The effective treatments were then tested for their impact on lettuce and basil in a split-plot experiment conducted in commercial NFT units. Crop yield, color, and nutrient content (chlorophyll and carotenoids) were measured throughout the crop life cycle. While all quaternary ammonium compounds (QAC), SaniDate 12.0 (200 ppm), Zorotol (5%), and Virkon (1%) eliminated Salmonella Typhimurium from commercial NFT surfaces, chlorine-based sanitizer treatments were statistically similar to water treatments on most surfaces. All chemical sanitizers impacted the yield, color, and nutritional value of lettuce and basil. SaniDate 12.0 (200 ppm) was the least detrimental to crops and was identified as a potential candidate for further validation in commercial hydroponic settings. The findings of this study will be translated into recommendations for the industry and will contribute to the development of future food safety guidelines and policies.

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Respiratory diseases caused by viruses are a serious global health threat. Although the use of hand sanitizers containing alcohol and synthetic antiseptic agents is recognized as an effective, simple, and low-cost measure to combat viral transmission, they can harm human health and the environment. Thus, this work aimed to study the efficacy of combining Camellia sinensis and Chamomilla recutita extracts in a skin- and eco-friendly leave-on hand sanitizer to prevent the spread of respiratory viruses. An oil-in-water emulsion containing C. recutita oily extract (5.0%), C. recutita glycolic extract (0.2%) and C. sinensis glycolic extract (5.0%) showed virucidal activity against HAdV-2 (respiratory virus) and two surrogate viruses of SARS-CoV-2 (HSV-1 and MVH-3), showing great potential to prevent the spread of respiratory viruses. These natural extracts combined are also promising to combat a broad spectrum of other viruses, in the form of antiseptic mouthwashes or throat sprays, surface disinfectants, and veterinary products, among others. Complementally, the developed hand sanitizer demonstrated efficacy against bacteria and fungus.

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CONTEXT: In this work, we explore the potential of 2D materials, particularly graphene and its derivatives, for eco-friendly electricity generation and air pollution reduction. Leveraging the significant surface area of graphene nanomaterials, the susceptibility of these graphene-based nanostructures to hazardous substances and their applicability in clean solar cell (SSC) devices were systematically investigated using density functional theory (DFT), as implemented within Gaussian 5.0 code. Time-dependent DFT (TD-DFT) was employed to characterize the UV-visible spectrum of unstrained nanostructures. Herein, we considered three potentially harmful gases-CO, NH3, and Br2. Adsorption calculations revealed a notable interaction between the pure graphene nanostructure and Br2 gas, while the S-doped counterpart exhibited reduced interaction. Saturated S-doped nanostructures demonstrated an enhanced affinity for NH3 and CO gases compared to their pure S-doped counterparts, attributed to the sulfur (S) atom facilitating gas molecule binding to the nanostructure's surface. Furthermore, simulations of the SSC device architecture indicated the superior performance of the pure graphene nanostructure in terms of light-harvesting efficiency, injection energy, and electron injection into the lower conduction band of CBM titanium dioxide (TiO2). These findings suggest a potential avenue for developing nanostructures tailored for SSC devices and gas sensors, offering a dual solution to address air pollution concerns. METHODS: Density function theory was used to compute the ground and excited state properties for pure and sulfur-doped graphene nanostructures. The hybrid function B3LYP with a 6-31G* basis set was utilized to describe the exchange correlation. Gauss Sum 2.2 software is used to estimate the density of state (DOS) for all structures under investigation.

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The use of flume tanks for tomato processing has been identified as a potential source of cross-contamination, which could result in foodborne illness. This study's objective was to assess the efficacy of peroxyacetic acid (PAA) at a concentration of ≤80 mg/L in preventing Salmonella enterica cross-contamination under various organic loads in a benchtop model tomato flume tank. The stability of 80 mg/L PAA at different chemical oxygen demand (COD) levels was also tested. Tomatoes were spot inoculated with a five-serovar rifampin-resistant (rif+) Salmonella cocktail (106 or 108 colony forming unit (CFU)/tomato). Inoculated (n = 3) and uninoculated (n = 9) tomatoes were introduced into the flume system containing 0-80 mg/L PAA and 0 or 300 mg/L COD. After washing for 30, 60, or 120 s, uninoculated tomatoes were sampled and analyzed for cross-contamination. All experiments were conducted in triplicate. Increasing the organic load (measured as COD) affected the stability of PAA in water with significantly faster dissociation when exposed to 300 mg/L COD. The concentration of PAA, inoculum level, COD levels, and time intervals were all significant factors that affected cross-contamination. Cross-contamination occurred at the high inoculum level (108 CFU/tomato) even when 80 mg/L PAA was present in the model flume tank, regardless of the organic load level. When the tomatoes were contaminated at a level of 106 CFU/tomato, concentrations as low as 5 mg/L of PAA were effective in preventing cross-contamination at 0 mg/L COD; however, 100 % tomatoes (9/9) were positive when the organic load increased to 300 mg/L COD. When the PAA concentration was increased to 10 mg/L, it effectively prevented cross-contamination in the tank, regardless of the presence of organic load. These results suggest that using PAA at concentrations below the maximum limit remains effective in limiting bacterial cross-contamination and offers a more environment-friendly option for tomato packinghouse operators.

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Background: While healthcare-associated infections (HAIs) affect approximately 3.2-6.5% of hospitalised patients in the US and Europe, improving hand hygiene (HH) could reduce HAI rates. Investigating HH is time-consuming and not always objective, and comprehensive, unbiased data is needed to develop effective strategies. Using electronic tools can provide new and detailed insights on the determinants of HH. Aim: To evaluate location-dependent usage of wall-mounted dispensers (WMDs) and point-of-care dispensers (POCs) using an electronic HH recording system. Methods: In this retrospective study, hand rub volumes were anonymously recorded for 931,446 disinfections from 17 wards in nine German hospitals using the electronic monitoring system NosoEx®. Number of disinfections and rub volumes of WMDs/POCs by ward and room type were analysed. Findings: Generally, WMDs were most prevalent. With >3 dispensers per bed and >20 disinfections per patient day, availability and use were highest in intensive care (ICU) and intermediate care (IMC), but here rub volumes from WMDs were lowest (∼2.0 mL). Although most dispensers are located in patient rooms (∼42%), they are more frequently used in hallways. In surgical ICUs, dispensers are often used in patient rooms, where contact with open wounds is common. About 3.6 mL of hand rub is used per disinfection in treatment rooms, the highest volume of all room types. Conclusion: Dispenser use was dependent on location, room type, ward specialisation and workflow. Optimising the location of hand rub dispensers (HRDs)s is not the only solution to improve HH, but can help reduce inconvenience, achieve more ergonomic workflows and better meet user needs.

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Leafy green surface microbiology studies often experience significant variations in results due to the heterogeneous nature of leaf surfaces. To provide a precise and controllable substitute, we microfabricated double-sided artificial leafy green phylloplanes using polydimethylsiloxane (PDMS) with a vinyl-terminated polyethylene glycol chain-based hydrophobicity modifier (PDMS-PEG) to modify PDMS hydrophobicity. We further tested the properties and applications of these artificial leaves, by examining the function of epicuticular wax, growth and survival of E. coli O157:H7 87-23 on the surface, and removal of attached E. coli cells via sanitation. The double-sided PDMS-PDMS-PEG leaves well-replicated their natural counterparts in macroscopic and microscopic structure, hydrophobicity, and E. coli O157:H7 87-23 attachment. After depositing natural epicuticular wax onto artificial leaves, the leaf surface wetting ability decreased, while E. coli O157:H7 87-23 surface retention increased. The artificial leaves supplied with lettuce lysate or bacterial growth media supported E. coli O157:H7 87-23 growth and survival similarly to those on natural leaves. In the sanitation test, the artificial lettuce leaves also displayed patterns similar to those of natural leaves regarding sanitizer efficiency. Overall, this study showcased the microfabrication and applications of double-sided PDMS-PDMS-PEG leaves as a replicable and controllable platform for future leafy green food safety studies.

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The present study aimed to assess the occurrence and counts of Staphylococcus aureus in Brazilian artisanal cheeses (BAC) produced in five regions of Brazil: Coalho and Manteiga (Northeast region); Colonial and Serrano (South); Caipira (Central-West); Marajó (North); and Minas Artisanal cheeses, from Araxá, Campos das Vertentes, Cerrado, Serro and Canastra microregions (Southeast). The resistance to chlorine-based sanitizers, ability to attach to stainless steel surfaces, and antibiogram profile of a large set of S. aureus strains (n = 585) were assessed. Further, a total of 42 isolates were evaluated for the presence of enterotoxigenic genes (sea, seb, sec, sed, see, seg, sei, sej, and ser) and submitted to typing using pulsed-field gel electrophoresis (PFGE). BAC presented high counts of S. aureus (3.4-6.4 log CFU/g), varying from 25 to 62.5%. From the S. aureus strains (n = 585) assessed, 16% could resist 200 ppm of sodium hypochlorite, whereas 87.6% produced strong ability to attach to stainless steel surfaces, corroborating with S. aureus ability to persist and spread in the environment. Furthermore, the relatively high frequency (80.5%) of multidrug-resistant S. aureus and the presence of enterotoxin genes in 92.6% of the strains is of utmost attention. It reveals the lurking threat of SFP that can survive when conditions are favorable. The presence of enterotoxigenic and antimicrobial-resistant strains of S. aureus in cheese constitutes a potential risk to public health. This result calls for better control of cheese contamination sources, and taking hygienic measures is necessary for food safety. More attention should be paid to animal welfare and hygiene practices in some dairy farms during manufacturing to enhance the microbiological quality of traditional cheese products.

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A number of biocidal disinfectant chemicals are used as household products to prevent spread of pathogens. People are commonly exposed to multiple chemicals through those disinfectants. However, effects of interactions (e.g., synergism) between disinfectants on human health outcomes have been rarely studied. In this study, we aimed to investigate associations of a mixture of chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT) and polyhexamethylene guanidine (PHMG), which had been used as humidifier disinfectants (HDs) in South Korea, with HD-associated lung injury (HDLI) in a Korean population (n = 4058) with HD exposure through use of HD products. Exposure to HD was retrospectively assessed by an interview-based standardized survey, and HDLI was determined by clinical assessment. After adjusting for covariates, PHMG-specific exposure indices (e.g., amount of use, indoor air concentration, and weekly exposure level) were dose-dependently associated with HDLI (their odds ratios for the comparison of third tertile versus first tertile were 1.95, 1.77, and 2.16, respectively). CMIT/MIT exposure was not observed to have a significant association with HDLI in a single chemical exposure model; however, associations between PHMG exposure and HDLI were strengthened by co-exposure to CMIT/MIT in combined chemical exposure models, where synergistic interactions between CMIT/MIT use and PHMG indices (amount of use and weekly exposure level) were observed (p-interaction in additive scale: 0.02 and 0.03, respectively). Our findings imply that adverse effects of PHMG exposure on lung injury among HD users might be worsened by co-exposure to CMIT/MIT. Given that plenty of household products contain disinfectants on global markets, epidemiological and toxicological investigations are warranted on interaction effects of co-exposure to disinfectants.

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Introducción: El consumo de desinfectantes de manos a base de alcohol ha aumentado significativamente después de la pandemia causada por el SARS-CoV-2. A pesar de la conclusión de la emergencia sanitaria declarada por la OMS en 2023, la costumbre de desinfectar las manos con geles sanitizantes a base de etanol ha sido adoptada a nivel mundial por la población. Dado que los métodos generales descritos en los compendios oficiales para la de-terminación del etanol, como la cromatografía de gases o la destilación, son laboriosos y no específicos para geles que contienen carbómero, este trabajo propone un método alternativo basado em la colorimetría de imágenes digitales. Método: La imagen digital (proporcionada por la reacción etanol-fenolftaleína) fue capturada y transformada en una señal analítica basada en el sistema de colores Rojo-Verde-Azul. Las adquisiciones de imágenes se realizaron utilizando un smartphone Samsung Galaxy J6, y las señales se generaron mediante el programa gratuito Photometrix Pro®. El método fue validado de acuerdo con las directrices de la ICH y se aplicó en muestras comerciales. Además, el método propuesto fue evaluado por su impacto ambiental utilizando la herramienta Índice del Proceso Analítico Verde (GAPI). Se generaron pictogramas utilizando el programa gratuito ComplexGAPI®.Resultados: El canal verde mostró una respuesta lineal en las curvas de calibración para concentraciones de etanol que van desde el 5 hasta el 40 % (p/p) en medio ácido. El método demostró linearidad, precisión, exactitud y robustez. Conclusiones: El método propuesto presentó como principales ventajas el uso de dispositivos de bajo costo y fáciles de manejar, así como un consumo reducido de reactivos, de acuerdo con los principios de la química analítica verde. (AU)

Introduction: The consumption of alcohol-based hand sanitizers has increased significantly after the pandemic caused by SARS-CoV-2. Despite the conclusion of the health emergency declared by the WHO in 2023, the habit of sanitizing hands with ethanol-based gel sanitizers has been globally adopted by the population. Since general methods described in official compendia for ethanol determination such as gas chromatography or distillation are laborious and not-specific to carbomer-containing gels, this work proposes an alternative method based on digital image colorimetry. Method: The digital image (provided by ethanol-phenolphthalein reaction) was captured and transformed into an analytical signal based on the Red-Green-Blue system. The image acquisitions were performed using a Samsung Galaxy J6 smartphone, and the signals were generated using the Photometrix Pro® free program. The method was validated in accordance with ICH and applied in commercial samples. Additionally, the proposed method was eval-uated for its environmental impact using the Green Analytical Process Index (GAPI) tool. Pictograms were generated using the ComplexGAPI® free program. Results: Green channel exhibited a linear response in the calibration curves for ethanol concentrations ranging from 5 to 40 % (w/w) in acidic medium. The method showed linearity, precision, accuracy, and robustness. Conclusions: The proposed method presented as main advantages the use of low-cost and easy-to-handle devices and reduced reagent consumption, in accordance with green analytical chemistry principles. (AU)

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Phenolic branched-chain fatty acid (PBC-FA) emulsion was produced by dissolving it in ethanol and mixing with water (pH 7). The resulting monodispersed emulsion droplets were approximately 200 nm in diameter. The stability of the emulsion was evaluated by storing it at 4 and 20 °C for 30 days. The antimicrobial activity of the PBC-FA emulsion was tested against Escherichia coli and Listeria innocua (8 log CFU/mL) by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using a microdilution method. The PBC-FA was effective against L. innocua with MIC and MBC of 14.1 µg/mL and caused membrane permeation as determined with SEM and Live/Dead cell assay, but was not effective against E. coli O157:H7 at the tested concentrations (5-250 µg/mL). We also evaluated PBC-FA emulsion's potential to be used as a wash against L. innocua inoculated on apples. The results showed that the 500 µg/mL PBC-FA emulsion with 5 % ethanol had equivalent antimicrobial activity (2-3 logs reductions) against L. innocua as the 20 µg/mL chlorine solution, a commonly used sanitizer. 500 µg/mL PBC-FA emulsion had better antimicrobial efficacy when organic matter (chemical oxygen demand: 9.0 g/L) was present compared to 20 µg/mL of chlorine. The effect of PBC-FA on the quality of the apples, was determined by measuring changes in color, firmness, and soluble solids content over a 14-day storage period at 20 °C. The quality of the apples was not affected by PBC-FA over the 14-day storage period, suggesting that PBC-FA emulsion can be used as a wash for apples without affecting their quality.

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Salmonella enterica is a prominent cause of foodborne disease in the United States. However, the mechanism and route of pathogen transmission that leads to Salmonella infection in commercial processing plants are poorly understood. This study aimed to investigate the effect of mixed-species biofilms on S. enterica survival and persistence under sanitizer stress [Quaternary ammonium compounds (QACs)] by analyzing 78 floor drain samples from a meat processing facility and three S. enterica strains (serovars Cerro, Montevideo, and Typhimurium) isolated from that facility and an unrelated source. The four test groups were as follows: control, QAC treatment, Salmonella addition, and QAC treatment with Salmonella addition. DNAs were extracted, and 16S rRNA gene based on the variable region V4 amplicon sequencing was performed to analyze the relative abundance, core microbiome, and Alpha and Beta diversity using the qiime2 pipeline. At the genus level, the Brochothrix (45.56%), Pseudomonas (38.94%), Carnobacterium (6.18%), Lactococcus (4.68%), Serratia (3.14%), and Staphylococcus (0.82%) were shown to be the most prevalent in all drain samples. The results demonstrate that the relative abundance of different bacterial genera was affected by both QAC treatment and Salmonella addition, with some genera showing increases or decreases in abundance. Notably, the correlation network was constructed to understand the relationships between the different bacteria. Nitrospira had the greatest number of connections in the floor drain environment network, with two negative and eight positive correlations. The results suggest that Nitrospira in the mixed-species biofilm community may play a role in converting ammonium in the QAC sanitizer into nitrites. Thus, Nitrospira could be a potentially important genus in providing sanitizer resistance to pathogen-encompassed mixed-species biofilms.IMPORTANCESalmonella contamination in meat processing facilities can lead to foodborne illness outbreaks. Our study characterized the microbiome dynamics in beef facility drains and their response to Salmonella addition and common sanitizer (QAC). Nitrospira could be an important genus in providing sanitizer resistance to pathogen-encompassed mixed-species biofilms. The results provide insight into the impact of mixed-species biofilms on Salmonella survival and persistence under sanitizer stress in meat processing facilities. The results highlight the need to consider mixed-species biofilm effects when developing targeted interventions to enhance food safety.

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